Phthalocyanines and their use in ink-jet printing

ABSTRACT

Compounds of Formula (1) and salts thereof: 
     
       
         
         
             
             
         
       
         
         
           
             wherein:
           M is 2H, Si, a metal, an oxymetal group, a hydroxymetal group or a halometal group;   Pc represents a phthalocyanine nucleus of formula;   
         
           
         
       
    
     
       
         
         
             
             
         
       
         
         
           
             R 1  is optionally substituted alkyl other than methyl: 
             R 2  is H, optionally substituted alkyl or optionally substituted aryl; 
             R 3  is H, optionally substituted alkyl or optionally substituted aryl; 
             R 4  is a group comprising a heterocycle and an ionisable group; 
             L is a direct bond or a divalent linking group; 
             x is 0.1 to 3.8; 
             y is 0.1 to 3.8; and 
             z is 0.1 to 3.8. Also compositions, inks, printed material and in-jet processes and cartridges.

This invention relates to compounds, compositions and inks, to printing processes, to printed materials and to ink-jet printer cartridges.

Ink-jet printing is a non-impact printing technique in which droplets of ink are ejected through a fine nozzle onto a substrate without bringing the nozzle into contact with the substrate.

Colour ink-jet printers typically use four different coloured inks; magenta, yellow, cyan, and black. Colours other than these may be obtained using differing combinations of these inks. Thus, for optimum print quality, the colourants used must be able to form an ink with a specific precise hue. This can be achieved by mixing colourants but is advantageously achieved by used a single colourant with the exact hue required.

While ink-jet printers have many advantages over other forms of printing and image development there are still technical challenges to be addressed. For example, there are the contradictory requirements of providing ink colorants that are soluble in the ink medium and yet do not run or smudge excessively when printed on paper. The inks need to dry quickly to avoid sheets sticking together after they have been printed, but they should not form a crust over the tiny nozzle used in the printer. Storage stability is also important to avoid particle formation that could block the tiny nozzles used in the printer especially since consumers can keep an ink-jet ink cartridge for several months.

With the advent of high-resolution digital cameras and ink-jet printers it is becoming increasingly common for consumers to print off photographs using an ink-jet printer. This avoids the expense and inconvenience of conventional silver halide photography and provides a print quickly and conveniently. However this use of ink-jet printers requires that the prints should display an outstanding fastness to light and common oxidising gases-such as ozone. Photographs, once printed, are often kept on display for years and it has been found that even apparently small changes in the light and ozone fastness of a print in a test system can correlate to a significant improvement in the fastness of the image in real life.

Another key factors in determining the colour appearance of an ink-jet print is the chroma intensity of the component colours and small changes in this can have a profound impact on the quality of the image, this is especially true when the image is a photographic reproduction.

There are many thousands of known colorants and few have the characteristics which enable them to be used in ink-jet inks.

Most cyan colorants used in ink-jet printing are based on phthalocyanines and problems of fading and shade change on exposure to light and contact with ozone are particularly acute with dyes of this class.

Phthalocyanines bearing sulfonate and sulfonamide substituents have found particular utility in ink-jet printing. These dyes are usually made by sulfonating a phthalocyanine pigment followed by chlorination and then amination/amidation, the resultant product carries sulfo and sulfonamide/substituted sulfonamide substituents in any susceptible position (for example see Schofield, J and Asaf, M in Journal of Chromatography, 1997, 770, pp 345-348). However we have found that certain phthalocyanines substituted only in the β-position display advantageous properties when used in ink-jet printing.

The present invention provides compounds of Formula (1) and salts thereof:

wherein:

-   -   M is 2H, Si, a metal, an oxymetal group, a hydroxymetal group or         a halometal group;     -   Pc represents a phthalocyanine nucleus of formula;

R¹ is optionally substituted alkyl other than methyl;

R² is H, optionally substituted alkyl or optionally substituted aryl;

R³ is H, optionally substituted alkyl or optionally substituted aryl;

R⁴ is a group comprising a heterocycle and an ionisable group;

L is a direct bond or a divalent linking group;

x is 0.1 to 3.8;

y is 0.1 to 3.8; and

z is 0.1 to 3.8.

M is preferably 2Li, 2Na, 2K, Mg, Ca, Ba, Al, Si, Sn, Pb, Rh, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, AlX, GaX, InX or SiX₂, where in X is OH or Cl, more preferably Sc, Ti, Va, Cr, Mn, Fe, Co, Zn, Ni and Cu, especially Cu or Ni and more especially Cu.

Preferably R¹ is optionally substituted C₂₋₈alkyl, more preferably optionally substituted C₂₋₆alkyl and especially optionally substituted C₂₋₄alkyl. It is particularly preferred that R¹ carries at least one substituent selected from the group consisting of —OH, —SO₃H, —CO₂H and —PO₃H₂.

Preferably R² is H or optionally substituted alkyl, more preferably H or optionally substituted C₁₋₄alkyl, particularly H or unsubstituted C₁₋₄alkyl, more particularly R² is H, methyl or ethyl, especially H or methyl and more especially H.

Preferably R³ is H or optionally substituted alkyl, more preferably H or optionally substituted C₁₋₄alkyl, particularly H or unsubstituted C₁₋₄alkyl, more particularly R³ is H, methyl or ethyl, especially H or methyl and more especially H.

Preferably R⁴ comprises a nitrogen heterocycle, more preferably R⁴ comprises a triazinyl radical.

Preferably R⁴ comprises an ionisable acid group more preferably an ionisable acid group selected from the group consisting of —SO₃H, —CO₂H and —PO₃H₂.

Preferably R⁴ is a triazinyl radical bearing substituents selected from the group consisting of —SO₃H, —CO₂H and —PO₃H₂.

It is especially preferred that R⁴ comprises a group of Formula (2)

wherein:

-   -   X is selected from the group consisting of —OR⁵, —SR⁵, —NR⁵R⁶;     -   Y is selected from the group consisting of —OR⁷, —SR⁷, —NR⁷R⁸;     -   R⁵, R⁶, R⁷ and R⁸ are independently H, optionally substituted         alkyl, optionally substituted aryl or optionally substituted         heterocyclyl provided that at least one of the groups         represented by R⁵, R⁶, R⁷ and R⁸ carries at least one         substituent selected from the group consisting of —SO₃H, —CO₂H         and —PO₃H₂.

Preferred groups represented by X and Y include —OH, —NHCH₃, —N(CH₃)₂, —NHC₂H₄SO₃H₂, —N(CH₃)C₂H₄SO₃H₂, —NC₃H₆SO₃H, —NHdisulfophenyl, —NHsulfophenyl, —NHcarboxyphenyl or —NHdicarboxyphenyl, —NHsulfonaphthyl, —NHdisulfonaphthyl, —NHtrisulfonaphthyl, —NHcarboxyonaphthyl, NHdicarboxyonaphthyl, NHtricarboxyonaphthyl-NHsulfoheterocyclyl, —NHdisulfoheterocyclyl or —NHtrisulfoheterocyclyl.

It is especially preferred that R⁴ comprises a group of Formula (3)

wherein:

-   -   R⁹ is H or optionally substituted C₁₋₄alkyl;     -   R¹⁰ is H or optionally substituted C₁₋₄alkyl;     -   R¹¹ is H or optionally substituted C₁₋₄alkyl;     -   R¹² is optionally substituted alkyl, optionally substituted aryl         or optionally substituted heterocyclyl carrying at least one         substituent selected from the group consisting of —SO₃H, —CO₂H         and —PO₃H₂.

Preferably R⁹ is H or unsubstituted C₁₋₄alkyl, more preferably R⁹ is H or methyl especially H.

Preferably R¹⁰ is H or unsubstituted C₁₋₄alkyl, more preferably R¹⁰ is H or methyl especially H.

Preferably R¹¹ is H or unsubstituted C₁₋₄alkyl, more preferably R¹¹ is H or methyl especially H.

In a preferred embodiment R⁹, R¹⁰ and R¹¹ are all independently either H or methyl, more preferably R⁹, R¹⁰ and R¹¹ are all H.

Preferably R¹² is optionally substituted aryl carrying at least one substituent selected from the group consisting of —SO₃H, —CO₂H and —PO₃H₂. More preferably R¹² is an aryl group (particularly a phenyl group) carrying 1 to 3, especially 2, —SO₃H groups.

L, the divalent linking group is preferably selected from the group comprising: optionally substituted alkylene, optionally substituted arylene, optionally substituted cycloalkenylene, and optionally substituted heterocyclylene (including optionally substituted heteroarylene). More preferably L comprises optionally substituted alkylene, especially optionally substituted C₁₋₁₂alkylene and more especially optionally substituted C₁₋₄alkylene. It is particularly preferred that L comprises a group of formula —C₁₋₄alkylene-Z; where Z is a hetero atom preferably N, it is especially preferred that L comprises a group of formula —C₂H₄—NR²⁰—, wherein R²⁰ is H or methyl.

Preferably x is 0.1 to 3, more preferably 0.2 to 2.0. In one preferred embodiment x is less than 1 and in another preferred embodiment x is greater than 1.

Preferably y is 0.1 to 3, more preferably 0.2 to 2.0. In one preferred embodiment y is less than 1.

Preferably z is 0.1 to 3.5, more preferably 0.5 to 3, especially 0.8 to 3.0 and more especially 1.0 to 3.

The sum of (x+y+z) is preferably 3 to 4, more preferably the sum of (x+y+z) is 4.

In a preferred embodiment the substituents represented by x, y and z are bound to the phthalocyanine ring only through the β-position on the phthalocyanine ring.

Preferred optional substituents which may be present on L, R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹ and R¹² are independently selected from: optionally substituted alkoxy (preferably C₁₋₄-alkoxy), optionally substituted aryl (preferably phenyl), optionally substituted aryloxy (preferably phenoxy), optionally substituted heterocyclic, polyalkylene oxide (preferably polyethylene oxide or polypropylene oxide), carboxy, phosphato, sulfo, nitro, cyano, halo, ureido, —SO₂F, hydroxy, ester, —NR^(a)R^(b), —COR^(a), —CONR^(a)R^(b), —NHCOR^(a), carboxyester, sulfone, and —SO₂NR^(a)R^(b), wherein R^(a) and R^(b) are each independently H or optionally substituted alkyl (especially C₁₋₄-alkyl). When L, R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸ or R¹² comprise a cyclic group said group may also carry an optionally substituted alkyl (especially C₁₋₄-alkyl) substituent. Optional substituents for any of the substituents described for L, R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹ and R¹² may be selected from the same list of substituents.

Particularly preferred compounds of Formula (1) are of Formula (4) and salts thereof

wherein:

-   -   R¹³ is optionally substituted C₂₋₄alkyl;     -   R¹⁴, R¹⁵, R¹⁶, R¹⁷ and R¹⁸ are each independently H or methyl;     -   R¹⁹ is aryl carrying 1 to 3 —SO₃H groups and optionally other         substituents;     -   R²⁰ is H or methyl;     -   L′ is optionally substituted C₁₋₄alkylene;     -   x is 0.1 to 3.8;     -   y is 0.1 to 3.8;     -   z is 0.1 to 3.8; and     -   x+y+z is in the range of 3 to 4.

Preferably R¹⁹ is aryl carrying 1 or 2 —SO₃H groups. More preferably R¹⁹ is phenyl carrying 1 or 2 —SO₃H groups, especially 2 —SO₃H groups.

Preferably L′ is unsubstituted C₁₋₄alkylene, especially —C₂H₄—.

Preferred optional substituents on R¹⁹ are as listed above though preferably R¹⁹ carries no substituents other than the —SO₃H groups.

Preferences for x, y and z and x+y+z are as described above.

In preferred compounds and salts thereof of Formula (4) the substituents represented by x, y and z are bound to the phthalocyanine ring only through the β-position on the phthalocyanine ring.

The compounds and salts thereof of Formula (1) are also preferably free from fibre reactive groups. The term fibre reactive group is well known in the art and is described for example in EP 0356014 A1. Fibre reactive groups are capable, under suitable conditions, of reacting with the hydroxyl groups present in cellulosic fibres or with the amino groups present in natural fibres to form a covalent linkage between the fibre and the dye. As examples of fibre reactive groups excluded from the compounds and salts thereof of Formula (1) there may be mentioned aliphatic sulfonyl groups which contain a sulfate ester group in beta-position to the sulfur atom, e.g. beta-sulfato-ethylsulfonyl groups, alpha, beta-unsaturated acyl radicals of aliphatic carboxylic acids, for example acrylic acid, alpha-chloro-acrylic acid, alpha-bromoacrylic acid, propiolic acid, maleic acid and mono- and dichloro maleic; also the acyl radicals of acids which contain a substituent which reacts with cellulose in the presence of an alkali, e.g. the radical of a halogenated aliphatic acid such as chloroacetic acid, beta-chloro and beta-bromopropionic acids and alpha, beta-dichloro- and dibromopropionic acids or radicals of vinylsulfonyl- or beta-chloroethylsulfonyl- or beta-sulfatoethyl-sulfonyl-endo-methylene cyclohexane carboxylic acids. Other examples of cellulose reactive groups are tetrafluorbcyclobutyl carbonyl, trifluoro-cyclobutenyl carbonyl, tetrafluorocyclobutylethenyl carbonyl, trifluoro-cyclobutenylethenyl carbonyl; activated halogenated 1,3-dicyanobenzene radicals; and heterocyclic radicals which contain 1, 2 or 3 nitrogen atoms in the heterocyclic ring and at least one cellulose reactive substituent on a carbon atom of the ring, for example a triazinyl halide.

Acid or basic groups on the compounds of Formula (1), particularly acid groups, are preferably in the form of a salt. Thus, the Formulae shown herein include the compounds in salt form.

Preferred salts are alkali metal salts, especially lithium, sodium and potassium, ammonium and substituted ammonium salts (including quaternary amines such as ((CH₃)₄N⁺) and mixtures thereof. Especially preferred are salts with sodium, lithium, ammonia and volatile amines, more especially sodium salts. Compounds of Formula (1) may be converted into a salt using known techniques.

The compounds and salts thereof of Formula (1) may exist in tautomeric forms other than those shown in this specification. These tautomers are included within the scope of the present invention.

The compounds and salts thereof of Formula (1) may be prepared by any method known in the art.

Preferably the compounds of Formula (1) are prepared by condensing a phthalocyanine carrying sulfonyl chloride groups and optionally sulfonic acid groups with compounds of formula HNR¹R² and HNR³-L-R⁴ wherein R¹, R², R³ and R⁴ are as hereinbefore defined. Many compounds of formula HNR¹R² are commercially available, for example taurine. Compounds of HNR³-L-R⁴ may be readily prepared by a person of ordinary skill. The condensation is preferably performed in water at a pH above 7. Typically the condensation is performed at a temperature of 30 to 70° C. and the condensation is usually complete in less than 24 hours. The compounds of formula HNR¹R² and HNR³-L-R⁴ may be used as a mixture or condensed sequentially.

Phthalocyanines carrying sulfonyl chloride groups and optionally sulfonic acid groups may be prepared by chlorosulfonating phthalocyanine using, for example, chlorosulfonic acid and optionally a chlorinating agent (e.g. POCl₃, PCl₅ or thionylchloride).

When it is required that the substituents represented by x, y and z should be bound to the phthalocyanine ring only through the β-position then preferably sulfonated phthalocyanine is prepared by cyclisation of 4-sulfophthalic acid or an analogue thereof. Preferred analogues of phthalic acid include, phthalonitrile, iminoisoindoline, phthalic anhydride, phthalimide or phthalamide. The cyclisation reaction is carried out in the presence of a suitable source of ammonia (if required), and (if required) a suitable metal salt, for example CuCl₂, and a base such as 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU).

It is particularly preferred that the compounds and salts thereof of Formula (1) are obtainable by a process that comprises cyclisation of 4-sulfophthalic acid or an analogue thereof.

The compounds and salts thereof of Formula (1) have attractive, strong cyan shades and are valuable colorants for use in the preparation of ink-jet printing inks. They benefit from a good balance of solubility, storage stability and fastness to water and light.

According to a second aspect of the present invention there is provided a composition comprising a compound of Formula (1) as described in the first aspect of the invention and a liquid medium.

Preferred liquid media include water, a mixture of water and organic solvent and organic solvent free from water. Preferably the liquid medium comprises a mixture of water and organic solvent or organic solvent free from water.

When the liquid medium (b) comprises a mixture of water and organic solvent, the weight ratio of water to organic solvent is preferably from 99:1 to 1:99, more preferably from 99:1 to 50:50 and especially from 95:5 to 80:20.

It is preferred that the organic solvent present in the mixture of water and organic solvent is a water-miscible organic solvent or a mixture of such solvents. Preferred water-miscible organic solvents include C₁₋₆-alkanols, preferably methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, n-pentanol, cyclopentanol and cyclohexanol; linear amides, preferably dimethylformamide or dimethylacetamide; ketones and ketone-alcohols, preferably acetone, methyl ether ketone, cyclohexanone and diacetone alcohol; water-miscible ethers, preferably tetrahydrofuran and dioxane; diols, preferably diols having from 2 to 12 carbon atoms, for example pentane-1,5-diol, ethylene glycol, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol and thiodiglycol and oligo- and poly-alkyleneglycols, preferably diethylene glycol, triethylene glycol, polyethylene glycol and polypropylene glycol; triols, preferably glycerol and 1,2,6-hexanetriol; mono-C₁₋₄-alkyl ethers of diols, preferably mono-C₁₋₄-alkyl ethers of diols having 2 to 12 carbon atoms, especially 2-methoxyethanol, 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)-ethanol, 2-[2-(2-methoxyethoxy)ethoxy]ethanol, 2-[2-(2-ethoxyethoxy)-ethoxy]-ethanol and ethyleneglycol monoallylether; cyclic amides, preferably 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, caprolactam and 1,3-dimethylimidazolidone; cyclic esters, preferably caprolactone; sulfoxides, preferably dimethyl sulfoxide and sulfolane. Preferably the liquid medium comprises water and 2 or more, especially from 2 to 8, water-miscible organic solvents.

Especially preferred water-miscible organic solvents are cyclic amides, especially 2-pyrrolidone, N-methyl-pyrrolidone and N-ethyl-pyrrolidone; diols, especially 1,5-pentane diol, ethyleneglycol, thiodiglycol, diethyleneglycol and triethyleneglycol; and mono-C₁₋₄-alkyl and C₁₋₄-alkyl ethers of diols, more preferably mono-C₁₋₄-alkyl ethers of diols having 2 to 12 carbon atoms, especially 2-methoxy-2-ethoxy-2-ethoxyethanol.

Examples of further suitable liquid media comprising a mixture of water and one or more organic solvents are described in U.S. Pat. No. 4,963,189, U.S. Pat. No. 4,703,113, U.S. Pat. No. 4,626,284 and EP-A425,150.

When the liquid medium comprises organic solvent free from water, (i.e. less than 1% water by weight) the solvent preferably has a boiling point of from 30° to 200° C., more preferably of from 40° to 150° C., especially from 50 to 125° C. The organic solvent may be water-immiscible, water-miscible or a mixture of such solvents. Preferred water-miscible organic solvents are any of the hereinbefore-described water-miscible organic solvents and mixtures thereof. Preferred water-immiscible solvents include, for example, aliphatic hydrocarbons; esters, preferably ethyl acetate; chlorinated hydrocarbons, preferably CH₂Cl₂; and ethers, preferably diethyl ether; and mixtures thereof.

When the liquid medium comprises a water-immiscible organic solvent, preferably a polar solvent is included because this enhances solubility of the mixture of phthalocyanine dyes in the liquid medium. Examples of polar solvents include C₁₋₄-alcohols.

In view of the foregoing preferences it is especially preferred that where the liquid medium is organic solvent free from water it comprises a ketone (especially methyl ethyl ketone) and/or an alcohol (especially a C₁₋₄-alkanol, more especially ethanol or propanol).

The organic solvent free from water may be a single organic solvent or a mixture of two or more organic solvents. It is preferred that when the liquid medium is organic solvent free from water it is a mixture of 2 to 5 different organic solvents. This allows a liquid medium to be selected that gives good control over the drying characteristics and storage stability of the ink.

Liquid media comprising organic solvent free from water are particularly useful where fast drying times are required and particularly when printing onto hydrophobic and non-absorbent substrates, for example plastics, metal and glass.

Preferred compositions according to the second aspect of the invention comprise:

-   -   (a) from 0.01 to 30 parts of a compound of Formula (1) according         to the first aspect of the invention; and     -   (b) from 70 to 99.99 parts of a liquid medium;         wherein all parts are by weight

Preferably the number of parts of (a)+(b)=100.

The number of parts of component (a) is preferably from 0.1 to 20, more preferably from 0.5 to 15, and especially from 1 to 5 parts. The number of parts of component (b) is preferably from 80 to 99.9, more preferably from 85 to 99.5, especially from 95 to 99 parts.

Preferably component (a) is completely dissolved in component (b). Preferably component (a) has a solubility in component (b) at 20° C. of at least 10%. This allows the preparation of liquid dye concentrates that may be used to prepare more dilute inks and reduces the chance of the dye precipitating if evaporation of the liquid medium occurs during storage.

The liquid media may of course contain additional components conventionally used in ink-jet printing inks, for example viscosity and surface tension modifiers, corrosion inhibitors, biocides, kogation reducing additives and surfactants which may be ionic or non-ionic.

Although not usually necessary, further colorants may be added to the ink to modify the shade and performance properties. Examples of such colorants include C.I. Direct Yellow 86, 132, 142 and 173; C.I. Direct Blue 307; C.I. Food Black 2; C.I. Direct Black 168 and 195; and C.I. Acid Yellow 23.

It is preferred that the composition according to the invention is ink suitable for use in an ink-jet printer. Ink suitable for use in an ink-jet printer is ink which is able to repeatedly fire through an ink-jet printing head without causing blockage of the fine nozzles.

Ink suitable for use in an ink-jet printer preferably has a viscosity of less than 20 cP, more preferably less than 10 cP, especially less than 5 cP, at 25° C.

Ink suitable for use in an ink-jet printer preferably contains less than 500 ppm, more preferably less than 250 ppm, especially less than 100 ppm, more especially less than 10 ppm in total of divalent and trivalent metal ions (other than any divalent and trivalent metal ions bound to a colorant of Formula (1) or any other colourant or additive incorporated in the ink).

Preferably ink suitable for use in an ink-jet printer has been filtered through a filter having a mean pore size below 10 μm, more preferably below 3 μm, especially below 2 μm, more especially below 1 μm. This filtration removes particulate matter that could otherwise block the fine nozzles found in many ink-jet printers.

Preferably ink suitable for use in an ink-jet printer contains less than 500 ppm, more preferably less than 250 ppm, especially less than 100 ppm, more especially less than 10 ppm in total of halide ions.

The inks may be incorporated in an ink-jet printer as a high concentration cyan ink, a low concentration cyan ink or both a high concentration and a low concentration ink. In the latter case this can lead to improvements in the resolution and quality of printed images. Thus the present invention also provides a composition (preferably an ink) where component (a) is present in an amount of 2.5 to 7 parts, more preferably 2.5 to 5 parts (a high concentration ink) or component (a) is present in an amount of 0.5 to 2.4 parts, more preferably 0.5 to 1.5 parts (a low concentration ink).

A third aspect of the invention provides a process for forming an image on a substrate comprising applying ink suitable for use in an ink-jet printer, according to the second aspect of the invention, thereto by means of an ink-jet printer.

The ink-jet printer preferably applies the ink to the substrate in the form of droplets that are ejected through a small orifice onto the substrate. Preferred ink-jet printers are piezoelectric ink-jet printers and thermal ink-jet printers. In thermal ink-jet printers, programmed pulses of heat are applied to the ink in a reservoir by means of a resistor adjacent to the orifice, thereby causing the ink to be ejected from the orifice in the form of small droplets directed towards the substrate during relative movement between the substrate and the orifice. In piezoelectric ink-jet printers the oscillation of a small crystal causes ejection of the ink from the orifice. Alternately the ink can be ejected by an electromechanical actuator connected to a moveable paddle or plunger, for example as described in International Patent Application WO00/48938 and International Patent Application WO00/55089.

The substrate is preferably paper, plastic, a textile, metal or glass, more preferably paper, an overhead projector slide or a textile material, especially paper.

Preferred papers are plain or treated papers which may have an acid, alkaline or neutral character. Glossy papers are especially preferred. Photographic quality papers are especially preferred.

Examples of commercially available premium papers include HP Premium Coated Paper, HP Photopaper™ (both available from Hewlett Packard Inc.); Stylus™ Pro 720 dpi Coated Paper, Epson Photo Quality™ Glossy Film, Epson Photo Quality™ Glossy Paper (all available from Seiko Epson Corp.); Canon HR 101 High Resolution™ Paper, Canon GP 201 Glossy™ Paper, Canon HG 101 and HG201 High Gloss™ Film, Canon PR101 (all available from Canon); Kodak Premium™ Photopaper, Kodak Premium™ InkJetpaper (available from Kodak); Konica Inkjet Paper QP™ Professional Photo Glossy, Konica Inkjet Paper QP™ Professional Photo 2-sided Glossy, Konica Inkjet Paper QP™ Premium Photo Glossy, Konica Inkjet Paper QP™ Premium Photo Silky (available from Konica).

A fourth aspect of the present invention provides a material preferably paper, plastic, a textile, metal or glass, more preferably paper, an overhead projector slide or a textile material, especially paper more especially plain, coated or treated papers printed with a compound as described in the first aspect of the invention, a composition as described in the second aspect of the invention or by means of a process as described in the third aspect of the invention.

It is especially preferred that the printed material of the fourth aspect of the invention is a print on a photographic quality paper printed using a process as described in the third aspect of the invention.

A fifth aspect of the present invention provides an ink-jet printer cartridge comprising a chamber and an ink suitable for use in an ink-jet printer wherein the ink is in the chamber and the ink is as defined in the second aspect of the present invention. The cartridge may contain a high concentration ink and a low concentration ink, as described in the second aspect of the invention, in different chambers.

A sixth aspect of the invention provides an amine of Formula (5) and salts thereof:

The invention is further illustrated by the following Examples in which all parts and percentages are by weight unless otherwise stated.

EXAMPLES Analysis of Dyes of Formula (1)

Confirmation of the number of substituents on dyes of Formula (1) is by mass spectrometry. Elemental analysis is used to determine the ratios of x to y+z. Thus, when the sum of x plus y and z is not exactly 4 this is thought to be due to the presence of impurities. The presence of these impurities and their effect on the estimated values of x, y and z would be well known to a person skilled in the art who would treat the experimentally determined values of x, y and z simply as indicative of the presence of these substituents. Also with some dyes according to the present invention it is not possible, using these methods, to discriminate between the different sulfonamide substituents. In these cases x and y are quoted as a sum of both sulfonamide groups i.e. (y+z).

Example 1 Preparation of

Stage 1 Preparation of Copper Phthalocyanine Tetra-β-Sulfonate

Potassium 4-sulfophthalic acid (56.8 g), urea (120 g), CuCl₂ (6.9 g), ammonium molybdate (1.2 g) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (7.5 g) were mixed in a reaction vessel. The mixture was warmed in stages (130° C./30 minutes, 150° C./30 minutes, 180° C./30 minutes, 220° C./30 minutes) over 2 hours and the melt which formed was stirred at 220° C. for a further 2 hours. The resultant solid was extracted 4 times with hot water (4×200 ml) and the extract was filtered to remove insoluble material. The filtrate was stirred at between 60° C.-70° C. and then sufficient NaCl was added to give a 7% salt solution. Stirring was continued and the precipitate was filtered, washed with a 10% salt solution (200 ml) and pulled dry by vacuum. The resultant damp solid (77.6 g) was slurried in acetone, filtered and dried, first at room temperature and then at 50° C.

Stage 2

Preparation of Amine A:

Cyanuric chloride (27.68 g) dissolved in actone (150 ml) was added to a slurry of ice/water (100 g/150 ml) at 0-5° C. A solution of 2,5-disulfoaniline (41.4 g) in water (150 ml) at pH 4 to 5 was then added dropwise. This reaction mixture was kept below 5° C. and stirred at pH 4 to 5 for 2 hrs. The pH was then adjusted to pH 7 with 2M sodium hydroxide, the temperature was raised to 20-25° C. and the reaction mixture was left for 1 hour. Ammonia (9.1 ml) was then added and the pH adjusted to pH 9 to 9.5 (with 2M sodium hydroxide) and the reaction mixture was stirred at room temperature overnight. The next day the reaction mixture was heated to 80° C. for 1 h, and then ethylenediamine (99 ml) was added and the reaction mixture was heated at 80° C. for a further 2 hrs. The reaction mixture was then cooled, sodium chloride was added to give a 20% solution, and the pH was lowered to 1 with concentrated HCl. The precipitate that formed was filtered off and washed with a 20% sodium chloride solution. The precipitate was then slurried in methanol at 60° C., filtered and dried to give the above product (56.1 g).

Stage 3

Preparation of the Title Product

Phosphorous oxychloride (5.16 g) was added dropwise to chlorosulfonic acid (86 g) over 5 to 10 minutes while keeping the temperature below 35° C. When all the Phosphorous oxychloride had been added copper phthalocyanine tetra-β-sulfonate, from Stage 1, (16 g) was added portion-wise while keeping the reaction temperature below 55° C. The reaction mixture was stirred at 50-60° C. for 15-20 minutes. The temperature of the reaction mixture was then gradually increased to 138-140° C. over 30 minutes, held at this temperature for 6.5 h and then the reaction mixture was allowed to cool and stirred overnight at room temperature. The mixture was added to a water/ice (100 ml/150 g) mixture and the resultant precipitate was filtered, washed with ice cold water and filtered. The dried solid (5 g) in water (200 ml) was then added to a mixture of amine A from Stage 2 (2 molar equivalents, 2.94 g), in water (50 ml) followed by one molar equivalent of 2,3-dihydroxypropylamine (0.33 g) at 0°-5° C. The resultant mixture was stirred at 0° to 5° C. and pH 9 to 9.5 for 1 hour maintaining the pH by the addition of 2M sodium hydroxide. The reaction mixture was then stirred at room temperature overnight. The next day the reaction mixture was heated to 60° C., held at this temperature for 1 hour and then cooled to 40° C. The reaction mixture was then salted with a 20% sodium chloride solution and the pH was lowered to pH 1 with concentrated HCl. The solid that precipitated was filtered, washed with a 20% solution of sodium chloride, dissolved in deionised water, dialysed, filtered and then dried at 70° C. to give the product. Elemental analysis of the product gave x=0.7 and (y+z)=3.2.

Example 2 Preparation of

The dye of Example 2 was prepared as described in Example 1 except that in Stage 3 one molar equivalent of 2,3-dihydroxypropylamine and one molar equivalents of amine A, from Stage 2, were used. Elemental analysis of the product gave x=2.2 and (y+z)=1.6.

Example 3 Preparation of

The dye of Example 3 was prepared as described in Example 1 except that in Stage 3 one molar equivalent of 2-hydroxyethylamine was used in place of 2,3-dihydroxypropylamine and one molar equivalent of amine A, from Stage 2, was used. Elemental analysis of the product gave x=3.4 and (y+z)=1.8.

Example 4 Preparation of

The dye of Example 4 was prepared as described in Example 1 except that in Stage 3 one molar equivalent of 2-hydroxyethylamine was used in place of 2,3-dihydroxypropylamine and two molar equivalents of amine A, from Stage 2, were used. Elemental analysis of the product gave x=1.8 and (y+z)=2.8.

Example 5 Preparation of

The dye of Example 5 was prepared as described in Example 1 except that in Stage 3 one molar equivalent of taurine was used in place of 2,3-dihydroxypropylamine and two molar equivalents of amine A, from Stage 2, were used. Elemental analysis of the product gave x=0.3 and (y+z)=3.4.

Example 6 Preparation of

The dye of Example 6 was prepared as described in Example 1 except that in Stage 3 one molar equivalent of taurine was used in place of 2,3-dihydroxypropylamine, in Stage 2, 3-sulfoaniline was used in place of 2,5-disulfoaniline and two molar equivalents of amine A, from Stage 2, were used in Stage 3. Elemental analysis of the product gave x=1.8 and (y+z)=2.2.

Examples 7 to 14

The dyes of Example 7 to 14 were prepared as described in Example 1 except that in Stage 3 the two amines used were as specified in the table below.

Preparation of Amine B

Amine B was prepared as in Example 1, stage 2 except dimethylamine was used in place of ammonia.

Amidation pH and Example Amine B Amine alkali used x y + z 7 1 molar 2,3- 9-9.5 0.1 2.6 equivalent dihydroxypropylamine 2 M NaOH 1 molar equivalent 8 1 molar 2,3- 9-9.5 equivalent dihydroxypropylamine 2 M NaOH 4 molar equivalent 9 1 molar 2,3- 9-9.5 0.2 2.4 equivalent dihydroxypropylamine 20% aq. (excess) 2,3-dihydroxypropylamine 10 0.5 molar 2,3- 9-9.5 equivalent dihydroxypropylamine 2 M NaOH 4 molar equivalent 11 1 molar 2-hydroxyethylamine 9-9.5 1.4 1.8 equivalent 1 molar equivalent 2 M NaOH 12 1 molar 2-hydroxyethylamine 9-9.5 0.7 1.6 equivalent 4 molar equivalent 2 M NaOH 13 0.5 molar 2-hydroxyethylamine 9-9.5 2.0 1.4 equivalent 4 molar equivalent 2 M NaOH 14 1 molar 2-hydroxyethylamine 9-9.5 2.2 1.2 equivalent (excess) 20% aq. 2-hydroxyethylamine

Examples 15 to 21

The dyes of Example 15 to 21 were prepared as described in Example 1 except that in Stage 3 the two amines used were as specified in the table below.

Preparation of Amine C

Amine C was prepared as in Example 1, stage 2 except 2-hydroxyethylamine was used in place of ammonia.

Amidation pH and Example Amine C Amine alkali used x y + z 15 1 molar 2-hydroxyethylamine 9-9.5 2.0 1.8 equivalent excess 30% aq. 2-hydroxyethylamine 16 1 molar 2-hydroxyethylamine 9-9.5 1.1 1.6 equivalent 3 molar equivalent 2 M NaOH 17 1 molar 2-hydroxyethylamine 8.5-9 2.3 1.6 equivalent 1 molar equivalent 2 M NaOH 18 2 molar 2-hydroxyethylamine 8.5-9 2.4 1.6 equivalent 2 molar equivalent 2 M NaOH 19 2 molar 2-hydroxyethylamine 9-9.5 2.2 1.4 equivalent 1 molar equivalent 2 M NaOH 20 1 molar 2,3-dihydroxypropylamine 9-9.5 1.1 2.0 equivalent 1 molar equivalent 2 M NaOH 21 1 molar 2,3-dihydroxypropylamine 9-9.5 1.5 1.4 equivalent 4 molar equivalent 2 M NaOH

Example 22

Prepared as in Example 1, stage 2 except 2,3-dihydroxypropylamine was used in place of ammonia.

Examples 23 to 26

Amine of Example Example 22 Amine pH x y + z 23 1 molar 2,3- 9-9.5 1.6 1.6 equivalent dihydroxypropylamine 2M NaOH 4 molar equivalent 24 1 molar 2,3- 9-9.5 1.4 2.0 equivalent dihydroxypropylamine 2M NaOH 1 molar equivalent 25 1 molar 2-hydroxyethylamine 9-9.5 2.0 1.6 equivalent 1 molar equivalent 2M NaOH 26 1 molar 2-hydroxyethylamine 9-9.5 1.7 1.4 equivalent 4 molar equivalent 2M NaOH Comparative Dyes 1 and 2

The comparative dyes were two of the market leading ink-jet cyan dyes Pro-Jet® Cyan 1 and Pro-Jet® Cyan 2 available from FUJIFILM Imaging Colorants Ltd.

Example 27 Preparation of Inks and Comparative Inks

Inks were prepared from the Comparative Dyes and the dyes of Examples 1, 8, 16 and 23 as shown in Table 1, by dissolving 3 g of a dye in 97 ml of a liquid medium consisting of 5 parts 2-pyrrolidone; 5 parts thiodiethylene glycol; 1 part Surfynol® 465 and 89 parts water and adjusting the pH to between pH 8 to 9 with sodium hydroxide. Surfynol® 465 is a surfactant from Air Products.

TABLE 1 Dye of Example Ink Example 1 Example Ink 1 8 Example Ink 2 16 Example Ink 3 23 Example Ink 4 Comparative Dye 1 Comparative Ink C1 Comparative Dye 2 Comparative Ink C2

Example 28 Ink-Jet Printing

Inks prepared as described above were filtered through a 0.45 micron nylon filter and then incorporated into empty print cartridges using a syringe.

These inks were then printed onto Epson Ultra Premium Glossy Photo Paper (SEC PM) and Canon Premium PR101 Photo Paper (PR101).

The prints so formed, at 70% depth, were tested for ozone fastness by exposure to 1 ppm ozone at 40° C., 50% relative humidity for 24 hrs in a Hampden 903 Ozone cabinet. Fastness of the printed ink to ozone is judged by the difference in the optical density before and after exposure to ozone.

Optical density measurements were performed using a Gretag spectrolino spectrophotometer set to the following parameters:

Measuring Geometry 0°/45° Spectral Range 380-700 nm Spectral Interval 10 nm Illuminant D65 Observer 2° (CIE 1931) Density Ansi A External Filler None

Ozone fastness was assessed by the percentage change in the optical density of the print, where a lower figure indicates higher fastness. Results are shown in Table 2

TABLE 2 Ink Example SEC PM PR 101 Example Ink 1 15.04 9.09 Example Ink 2 5.69 3.76 Example Ink 3 3.82 1.42 Example Ink 4 7.63 5.07 Comparative Ink C1 52.94 38.98 Comparative Ink C2 54.17 39.16

Table 2 shows that the ink of the present invention have higher ozone fastness than the comparative dyes.

Further Inks

The inks described in Tables A and B may be prepared wherein the Compound described in the first column is the Compound made in the above Example of the same number. Numbers quoted in the second column onwards refer to the number of parts of the relevant ingredient and all parts are by weight. The inks may be applied to paper by thermal or piezo ink-jet printing.

The following abbreviations are used in Tables A and B:

PG = propylene glycol DEG = diethylene glycol NMP = N-methyl pyrrolidone DMK = dimethylketone IPA = isopropanol MEOH = methanol 2P = 2-pyrrolidone MIBK = methylisobutyl ketone P12 = propane-1,2-diol BDL = butane-2,3-diol CET= cetyl ammonium bromide PHO = Na₂HPO₄ and TBT = tertiary butanol TDG = thiodiglycol

TABLE A Dye Na Example Content Water PG DEG NMP DMK NaOH Stearate IPA MEOH 2P MIBK 1 2.0 80 5 6 4 5 2 3.0 90 5 5 0.2 3 10.0 85 3 3 3 5 1 4 2.1 91 8 1 5 3.1 86 5 0.2 4 5 6 1.1 81 9 0.5 0.5 9 1 2.5 60 4 15 3 3 6 10 5 4 2 5 65 20 10 1 2.4 75 5 4 5 6 5 2 4.1 80 3 5 2 10 0.3 1 3.2 65 5 4 6 5 4 6 5 1 5.1 96 4 1 10.8 90 5 5 1 10.0 80 2 6 2 5 1 4 1 1.8 80 5 15 1 2.6 84 11 5 1 3.3 80 2 10 2 6 1 12.0 90 7 0.3 3 1 5.4 69 2 20 2 1 3 3 1 6.0 91 4 5

TABLE B Dye Example Content Water PG DEG NMP CET TBT TDG BDL PHO 2P PI2 1 3.0 80 15 0.2 5 2 9.0 90 5 1.2 5 3 1.5 85 5 5 0.15 5.0 0.2 4 2.5 90 6 4 0.12 5 3.1 82 4 8 0.3 6 6 0.9 85 10 5 0.2 1 8.0 90 5 5 0.3 2 4.0 70 10 4 1 4 11 1 2.2 75 4 10 3 2 6 1 10.0 91 6 3 1 9.0 76 9 7 3.0 0.95 5 1 5.0 78 5 11 6 1 5.4 86 7 7 1 2.1 70 5 5 5 0.1 0.2 0.1 5 0.1 5 1 2.0 90 10 1 2 88 10 1 5 78 5 12 5 1 8 70 2 8 15 5 1 10 80 8 12 1 10 80 10 

1. Compounds of Formula (1) and salts thereof:

wherein: M is Cu or Ni; Pc represents a phthalocyanine nucleus of formula;

R¹ is optionally substituted alkyl other than methyl; R² is H, optionally substituted alkyl or optionally substituted aryl; R³ is H, optionally substituted alkyl or optionally substituted aryl; R⁴ is a group comprising a heterocycle and an ionisable group; L is a direct bond or a divalent linking group; x is 0.1 to 3.8; y is 0.1 to 3.8; wherein the substituents represented by x, y and z are bound to the phthalocyanine ring only through the β-position and the compounds of formula (1) and salts thereof are prepared by a process which comprises cyclisation of appropriate β-sulfo substituted phthalic acid, phthalonitrile, iminoisoindoline, phthalic anhydride, phthalimide or phthalamide optionally in the presence of a suitable nitrogen source, a copper or nickel salt and a base followed by chlorination and then reaction with groups of formula HNR¹R² and HNR³-L-R⁴ wherein R¹, R², R³ and R⁴ are as hereinbefore defined.
 2. Compounds and salts thereof according to claim 1 wherein M is Cu.
 3. Compounds and salts thereof according to claim 1 wherein R¹ is optionally substituted C₂₋₆alkyl.
 4. Compounds and salts thereof according to claim 1 wherein R¹ carries at least one substituent selected from the group consisting of —OH, —SO₃H, —CO₂H and —PO₃H₂.
 5. Compounds and salts thereof according to claim 1 wherein R² is H or methyl.
 6. Compounds and salts thereof according to claim 1 wherein R³ is H or methyl.
 7. Compounds and salts thereof according to claim 1 wherein R⁴ comprises a nitrogen heterocycle.
 8. Compounds and salts thereof according to claim 1 wherein R⁴ comprises an ionisable acid group selected from the group consisting of —SO₃H, —CO₂H and —PO₃H₂.
 9. Compounds and salts thereof according to claim 1 wherein R⁴ is a triazinyl radical bearing substituents selected from the group consisting of —SO₃H, —CO₂H and —PO₃H₂.
 10. Compounds and salts thereof according to claim 1 wherein R⁴ comprises a group of Formula (2)

wherein: X is selected from the group consisting of —OR⁵, —SR⁵, —NR⁵R⁶; Y is selected from the group consisting of —OR⁷, —SR⁷, —NR⁷R⁸; R⁵, R⁶, R⁷ and R⁸ are independently H, optionally substituted alkyl, optionally substituted aryl or optionally substituted heterocyclyl provided that at least one of the groups represented by R⁵, R⁶, R⁷ and R⁸ carries at least one substituent selected from the group consisting of —SO₃H, —CO₂H and —PO₃H₂.
 11. Compounds and salts thereof according to claim 1 wherein R⁴ comprises a group of Formula (3)

wherein: R⁹ is H or optionally substituted C₁₋₄alkyl; R¹⁰ is H or optionally substituted C₁₋₄alkyl; R¹¹ is H or optionally substituted C₁₋₄alkyl; R¹² is optionally substituted alkyl, optionally substituted aryl or optionally substituted heterocyclyl carrying at least one substituent selected from the group consisting of —SO₃H, —CO₂H and —PO₃H₂.
 12. Compounds and salts thereof according to claim 1 wherein L comprises optionally substituted alkylene.
 13. Compounds and salts thereof according to claim 1 wherein L comprises a group of formula —C₁₋₄alkylene-Z; where Z is a hetero atom.
 14. Compounds and salts thereof according to claim 1 wherein L comprises a group of formula —C₂H₄—NR²⁰—, wherein R²⁰ is H or methyl.
 15. Compounds and salts thereof according to claim 1 wherein (x+y+z) is
 4. 16. Compounds according to claim 1 of Formula (4) and salts thereof

wherein: R¹³ is optionally substituted C₂₋₄alkyl; R¹⁴, R¹⁵, R¹⁶, R¹⁷ and R¹⁸ are each independently H or methyl; R¹⁹ is aryl carrying 1 to 3 —SO₃H groups and other optional substituents; R²⁰ is H or methyl; L′ is optionally substituted C₁₋₄alkylene; x is 0.1 to 3.8; y is 0.1 to 3.8; z is 0.1 to 3.8; x+y+z is in the range of 3 to 4; and wherein the substituents represented by x, y and z are bound to the phthalocyanine ring only through the β-position and the compounds of formula (1) and salts thereof are obtainable by a process which comprises cyclisation of appropriate β-sulfo substituted phthalic acid, phthalonitrile, iminoisoindoline, phthalic anhydride, phthalimide or phthalamide optionally in the presence of a suitable nitrogen source, a copper or nickel salt and a base followed by chlorination and then reaction with groups of formula HNR¹R² and HNR³-L-R⁴ wherein R¹, R², R³ and R⁴ are as hereinbefore defined.
 17. A composition comprising a compound of Formula (1) as described in claim 1 and a liquid medium.
 18. A composition according to claim 17 wherein the liquid medium comprises a mixture of water and organic solvent or organic solvent free from water.
 19. A composition according to claim 17 which is ink suitable for use in an ink-jet printer.
 20. A process for forming an image on a substrate comprising applying ink suitable for use in an ink-jet printer, according to claim 19, thereto by means of an ink-jet printer.
 21. A material printed with a compound as described in claim
 1. 22. A material according to claim 21 which is a print on a photographic quality paper printed by a process comprising applying ink suitable for use in an ink-jet printer by means of an ink-jet printer, wherein the ink is a composition comprising a compound of Formula (1) and a liquid medium.
 23. An ink-jet printer cartridge comprising a chamber and an ink suitable for use in an ink-jet printer wherein the ink is in the chamber and the ink is as defined in claim
 19. 24. An amine of Formula (5) and salts thereof: 